Process of finishing the edges of glass sheets



Aug. 5 1924.

A. C. HILEMAN PROCESS OF FINISHING'THE EDGES OF GLASS SHEETS Filed June 5. 1924 Patented Aug. 5, 1924 UNETED STATES 1,503,586 PATENT OFFICE.

AUSTIN C. HILEMAN, 0F FORD CITY, PENNSYLVANIA, ASSIGNOR T0 PITTSBURGH PLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

PROCESS OF FINISHING THE EDGES OF GLASS SHEETS.

Application filed June 5,

To all whom it may concern:

Be it known that I, AUs'rIN C. HILEMAN, a citizen of the United States, and a resident of Ford City, in the county of Armstrong and State of Pennsylvania, have made a new and useful Invention in Improvements in a Process for Finishing the Edges of. Glass Sheets, of which the following is a specification. v

The invention relates to a process for finishing the edges of glass sheets, such as the plates employed in wind shields for automobiles, and it has for its bbjects-the provision of a process whereby the edges may be finished or smoothed more rapidly and cheaply than has heretofore been done.

Heretofore the practice'has been to grind I the edges of the sheet smooth and true by holding it in a vertical plane over a grinding disc or flat wheel revolving in a horizontal plane. The edge was thus brought into contact with the upper surface of the disc and the necessary grinding accomplished. The present invention is designed to do away with this relatively slow and expensive procedure, requiring as it does, much manual labor of a skilled operator. The present process permits the smoothing of the edges of a large number of sheets simultaneously and without the necessity of manipulating the individual sheets and without the grinding machinery required by the old practice. The practice of the process is illustrated in the accompanying drawing, wherein:

The figure is a side elevation showing a series of sheets positioned upon a truck and having their upper edges treated in accordance with the present invention.

Referring to the drawing, 1 is a truck provided with the wheels 2 and having at one side the upright wall 3, protected upon its inner side by the metal plate 4. 6 is the nozzle connected by means of a hose with a sand blasting apparatus which may be of any approved type.

In the practice of the invention the plates of glass, whose edges are to be finished or treated, are stacked upon the truck 1 with their upper edges lying in substantially the same plane. In order to have the plates stand in upright position while being placed upon the truck, and without the necessity of holding them in such position, the wall 3 at the end of the truck is made slightly 1924. Serial No. 718,018.

inclined as illustrated. The sheets are preferably all of the same size, but the edges, produced by trimming or cutting the glass by means of a diamond or other cutter, are not perfectly true and have many sharp projections and angles, thus requiring the finishmg operation. As stated heretofore, this finishing operation has been heretofore accomplished by grinding the edges of the sheets separately upon the grindingwheel, this requiring a large amount of labor and considerable skill. After the sheets have been stacked up as illustrated in the drawing, preferably to the number of a hundred or more where the sheets are of relatively small size, such as are employed in wind shields, the truck is moved so as to bring it adjacent the wall or support 7 and a holding member 8 is introduced between the wall and the last sheet of the stack, this member being pressed down firmly to bring the sheets into tight engagement with each other and hold them securely in position. The

sand .blast is now applied to the upper surapproximates that secured heretofore by the 7 use of a grinding wheel. The expense of finishing by this method is only a small fraction of that of the old process. The process is also much more rapid, requires less skill upon the part of the operator and-dispenses with the more or less expensive grinding machinery heretofore employed.

i If desired, he side edges of the sheets may be finished in the same manner as the top edges without changing the position of such sheets, or the sheets may be turned degrees to bring the side edges uppermost before applying the sand blast, and the invention contemplates various methods of handling the sheets and treating them aside from the particular one illustrated. In certain types of wind shields it is necessary to finish only one edge, whilejn others, it may be. desirable to finish-the side and bottom edges, in which case the procedure would be modified to meet the requirements, It may also be desirable to smooth the corners of the sheets at their upper edges by the sand blast, and this can be done by inclining the sheets to a greater extent so as to expose not-only the upper surface of the edges but also the corners of such edges. This secures the removal of one sharp corner of each sheet, and to secure the removal of the other, the sheets are tilted in the opposite di rection and the sand blast again applied. Various other possible modifications of the method of operation to meet special conditions will be readily apparent to those skilled in the art.

What I claim is:

The process of finishing the edges of glass sheets which consists in placing a series of the plates side by side with their adjacent side surfaces in opposition and close together and with the edges to be treated in substantial alignment, and then applying a sand blast to the said edges.

In testimony whereof, I have hereunto subscribed my name this second day of June,

AUSTIN O. HILEMAN. 

